Hard I have a bump on my left shoulder and pain that travels down the arm.

[JocelynMP]

One night about a week ago I was laying in bed and noticed my shoulder really hurt. When I examined my shoulder it seems that there was a bone sticking out farther than it should. The pain is constant and seems to travel down my arm. At first I thought it may have been AC separation, but I got an x-ray and it came back fine. I also have an ultrasound booked to see if it is something wrong with the tissue but my doctor seems a little unsure. I have no idea what is going on I am 17 and never had a serious injury to my shoulder that I know of. The only possible thing I can think of that is damaging my shoulder is carrying my heavy backback over a hour every day. I am pretty healthy though I think I should eat a bit more and I get over one hour of exercise daily. The only medication I am on is 20mg of fluoxetine and 54mg of concerta to help with my anxiety and ADHD. If you have any idea about what may be going on please tell me the pain has been bugging me for over a week so far and it is interrupting my sleep as well as distracting me from my studies.

Thanks,